Chronic lung disease and the pulmonary hemodynamics : a single center retrospective study

Background and Aims: Once chronic lung disease (CLD) patients develop pulmonary hypertension (PH), their prognosis worsen. To investigate the tendency of pulmonary hemodynamics in CLD, we conducted a single center retrospective observational study. Methods: From March 2014 to December 2016, CLD patients who had characteristic symptoms of PH such as dyspnea on exertion underwent transthoracic echocardiography (TTE). We performed right heart catheterization (RHC) to those with high estimated right ventricular pressure (eRVP) to measure mean pulmonary artery pressure (PAPm) and analyzed the correlation with other indexes; arterial blood gas (ABG) parameters and radiographic findings. Results: Twenty four patients were enrolled (median age; 70.5 yearold, male; 58%). Median eRVP was 38mmHg (29-100mmHg) and median PAPm was 20.5mmHg. Patient distribution by PAPm was as follows: ≥25mmHg, 16%, 20-24mmHg, 33% and <20mmHg, 50%. There were high correlation between eRVP and PAPm. Radiographic findings; diameter of right descending pulmonary artery (PA), abrupt tapering of the peripheral vessels in chest X-ray and diameter of PA and PA/ aorta diameter ratio in chest computer tomography and ABG; PaO2, PaCO2 and HCO3 parameters showed middle to strong correlations with PAPm. Conclusions: In this study, patients who met the criteria of PH were limited to 13%. However, there were 50% patients showing PAPm≥20mmHg. Since previous studies showed poor prognosis for patients with PAPm ≥20mmHg, we should concern early intervention for this certain amount of population. In our patients, not only eRVP but other indexes showed correlation with PAPm. Along with TTE, radiographic and ABG findingsmay be simple daily objective parameters of PH in CLD patients.